The present invention relates to equipment for forming ordered groups of articles.
The invention has been developed with particular attention to its possible application in the field of automatic packaging systems for products such as food products.
In this context, the problem often arises of how to ensure that products (such as, for example spherical chocolates of the type described in the patent EP-A-0 0 083 324) issuing from a production line in an almost continuous carpet which does, however, have some irregularities, may be gathered into ordered groups for packaging.
Arrangements put forward until today to solve this problem have usually required a sequence of somewhat complicated manipulations. The incoming flow of articles (which, as stated above, may be fairly irregular or disorganised) is subjected to a series of operations aimed at putting it in order, for example by forming rows or lines and then removing articles in an ordered manner until, after further manipulations, they form groups each including a predetermined number of articles.
In practice, however, such arrangements involve attempts to reconcile different, often opposing requirements.
Firstly, manipulations (which should be as few as possible) are carried out on articles which are moving through the packaging plant at a speed reflecting the output of the production plant itself. This rate tends to increase as plants become more sophisticated.
In addition, the products being handled (we refer in particular to food products, especially confectionery) may often be fairly fragile and liable to be damaged as a result of excessive shocks suffered during handling operations.
The need to follow particular aesthetic guidelines when packing the articles also means that they may need to be arranged in groupings which are difficult to achieve, with regard both to the number of articles in each group and to their positioning relative to each other. This is the case, for example, of packaging in which a relatively large number of spherical pralines (typically seven or eight) are aligned in a group intended to be inserted in a tubular package of the type known as a flow-pack.
A final consideration is that it is desirable for the equipment which is to form the groups of articles to be readily adaptable to vary the characteristics of the groups of articles (so-called format-change operations) for example, to switch from the formation of lines of eight articles to the formation of lines of six or ten articles.